A path traversal attack (also known as directory traversal) aims to access files and directories that are stored outside the web root folder. By manipulating variables that reference files with “dot-dot-slash (../)” sequences and its variations or by using absolute file paths, it may be possible to access arbitrary files and directories stored on the file system including application source code or configuration and critical system files. It should be noted that access to files is limited by system operational access control (such as in the case of locked or in-use files on the Microsoft Windows operating system).
This attack is also known as “dot-dot-slash”, “directory traversal”, “directory climbing” and “backtracking”.
Holm's default Web application scan profile will include HID-3-5-10133, which provides two different methods to find Path Traversal vulnerabilities.
- Small Payload List of well-known files
- Detection Based on string matches in responses
- If our plugin finds a Path Traversal vulnerability, it also tries to check if it could
escalate that into a Local File Inclusion RCE (via Log Poisoning)
This option could be enabled manually through UI in the web application scan profile:
First, it runs the basic method and then runs the advanced method
- Big Payload List (increase in total scan duration)
- Detection Based on response lengths (Possible False positives)
Why we combined Directory Traversal + Local File Inclusion into one HID? (Path Traversal)
Local File inclusion vulnerability: the resource is Loaded and Executed in the context of the current application.
Impact: Possible Remote Code Execution
Directory traversal vulnerability: Only gives you the ability to read the resource.
Impact: Information Disclosure
We cover Remote File Inclusion vulnerability in a separate HID and replace HID here